EXTRACTS T110M PBOCEEDINGS. 



lxxvii 



never before taken fully into account, but which has now been 

 forced upon my observation by its (supposed) result and analogous 

 things. There may or may not be anything in it ; but I humbly 

 submit it as a question to be tested and solved by others, if the 

 Committee deem it worthy of investigation. 



Is it possible ultimately to succeed in crosses between species 

 which, at first, resisted such cross, from the persistent act of in- 

 oculation of the stigma of the one by the pollen of the other ? 



You may remember noticing in the paper I have referred to 

 (read by me before the Botanical Society of Edinburgh) my 

 intended attempt to accomplish the same end by first ingrafting 

 the one species upon the other, the Azalea, say, upon the Rhodo- 

 dendron, and thus (the fluids of the stock being infused into the 

 scion) make them of one blood, and, so predisposed, induce a cross 

 of the latter on the former species. But this grafting process 

 would involve a tract of coming time which the experiments which 

 I now proposed will greatly shorten. 



At first sight, it may appear that the transfusion of a principle 

 communicated by a few grains of pollen, is utterly inadequate so 

 to affect the seed-bearing plant. But it has been again and again 

 suggested to me by analogous results ; e.g. I found (as given in an 

 article I wrote some dozen years ago, and quoted by Dr. Lindley 

 in his second edition of ' Theory and Practice ') a large portion of 

 the blooms of a white-lowered Calceolaria became flushed pink 

 from one or two blooms being inoculated with a crimson-coloured 

 variety. I may also allude to the Breadalbane Blotched Ash, com- 

 municated by me to Mr. Darwin, and cited in vol. i. p. 394 of his 

 latest work, ' Animals and Plants under Domestication,' and other 

 similar instances there noticed by him of variegation being pro- 

 duced on the stock. These were all, however, cases of budding or 

 grafting, but to which that of inoculation is akin. 



Now, ere I close, I may further explain that I made this same 

 Indian Azalea {A. stella) the subject, last year, of many crosses by 

 different JRJwdodendra, besides H. JEclgwortliii, two of which only 

 succeeded, namely, crosses by It. AucJdandii, of which, I may ob- 

 serve, I pulled the seeds too early, and so have only raised two 

 plants. And here I may observe further, that I have found that 

 the seeds of such extreme crosses take double the time which the 

 normal seeds require to ripen. But it is proper to mention that 

 I observed in the attempted Udgworthii-cross of last year, that 

 from one of the pods so crossed there was a continuous exudation 



